- An Expeditious Approach to Tetrazoles from Amides Utilizing Phosphorazidates
-
A novel method was developed for the synthesis of tetrazoles from amides utilizing diphenyl phosphorazidate or bis(p-nitrophenyl) phosphorazidate as both the activator of amide-oxygen for elimination and azide source. Various amides were converted into th
- Ishihara, Kotaro,Shioiri, Takayuki,Matsugi, Masato
-
supporting information
p. 6244 - 6247
(2020/07/24)
-
- Substituent-dependent coordination modes of 1-methyl-5-R-tetrazoles in their cupric chloride complexes
-
A series of cupric chloride complexes with 1-methyl-5-R-tetrazole ligands, where R = NH2, t-Bu, Ph, MeS, CH[dbnd]CH2, MeSO2, were synthesized by interaction of CuCl2·2H2O with the above ligands LNH2, LtBu, LPh, LMeS, LVin, and LMeSO2, respectively. The obtained complexes [Cu(LNH2)3Cl2]·H2O (1), [Cu(LtBu)2Cl2] (2), [Cu(LPh)2Cl2] (3), [Cu(LMeS)2Cl2] (4), [Cu(LVin)Cl2]n (5), and [Cu(LMeSO2)(H2O)Cl2]n (6) were characterized by single crystal X-ray analysis. The effect of C5-substituent on coordination modes of tetrazole ligands and structural motifs of complexes was observed. Complexes 1–4 are mononuclear, with the tetrazole ring N4 coordination. Complex 5 presents 1D coordination polymer, formed at the expense of triple bridge between two neighboring copper(II) cations (double chlorido bridge and the tetrazole ring N3,N4-bridge). In 6, being also 1D coordination polymer, coordination chains are composed of alternating Cu(LMeSO2)2 and Cu(H2O)2 fragments linked by double chlorido bridges. Ligand LMeSO2 shows N3 coordination, being rare among 1,5-disubstituted tetrazoles. The influence of the nature of C5 substituents on coordination features of the obtained complexes is discussed by using quantum-chemical calculations of the electronic structure and basicity of the ligands.
- Voitekhovich, Sergei V.,Lyakhov, Alexander S.,Matulis, Vadim E.,Ivashkevich, Ludmila S.,Ivashkevich, Oleg A.
-
p. 100 - 110
(2019/02/19)
-
- An Environmentally Friendly Method for N-Methylation of 5-Substituted 1H-Tetrazoles with a Green Methylating Reagent: Dimethyl Carbonate
-
An environmentally friendly method was established for the N-methylation of the 5-substituted 1H-tetrazoles with a green reagent: DMC. DABCO was the optimal catalyst, and hazardous chemicals were avoided in this protocol. A plausible catalytic mechanism is proposed, which consists of a DABCO-activated process and a thermally induced rearrangement of tetrazole carbamates.
- Xie, Aming,Zhang, Qiang,Liu, Yangyang,Feng, Liandong,Hu, Xinyu,Dong, Wei
-
p. 1483 - 1487
(2015/10/06)
-
- Iridium(III) complexes with phenyl-tetrazoles as cyclometalating ligands
-
Ir(III) cationic complexes with cyclometalating tetrazolate ligands were prepared for the first time, following a two-step strategy based on (i) a silver-assisted cyclometalation reaction of a tetrazole derivative with IrCl3 affording a bis-cyclometalated solvato-complex P ([Ir(ptrz)2(CH3CN)2]+, Hptrz = 2-methyl-5-phenyl-2H-tetrazole); (ii) a substitution reaction with five neutral ancillary ligands to get [Ir(ptrz)2L]+, with L = 2,2′-bypiridine (1), 4,4′-di-tert-butyl-2,2′-bipyridine (2), 1,10-phenanthroline (3), and 2-(1-phenyl-1H-1,2,3-triazol-4-yl)pyridine (4), and [Ir(ptrz)2L2]+, with L = tert-butyl isocyanide (5). X-ray crystal structures of P, 2, and 3 were solved. Electrochemical and photophysical studies, along with density functional theory calculations, allowed a comprehensive rationalization of the electronic properties of 1-5. In acetonitrile at 298 K, complexes equipped with bipyridine or phenanthroline ancillary ligands (1-3) exhibit intense and structureless emission bands centered at around 540 nm, with metal-to-ligand and ligand-to-ligand charge transfer (MLCT/LLCT) character; their photoluminescence quantum yields (PLQYs) are in the range of 55-70%. By contrast, the luminescence band of 5 is weak, structured, and blue-shifted and is attributed to a ligand-centered (LC) triplet state of the tetrazolate cyclometalated ligand. The PLQY of 4 is extremely low (a nonemissive triplet metal-centered ( 3MC) state. In rigid matrix at 77 K, all of the complexes exhibit intense luminescence. Ligands 1-3 are also strong emitters in solid matrices at room temperature (1% poly(methyl methacrylate) matrix and neat films), with PLQYs in the range of 27-70%. Good quality films of 2 could be obtained to make light-emitting electrochemical cells that emit bright green light and exhibit a maximum luminance of 310 cd m-2. Tetrazolate cyclometalated ligands push the emission of Ir(III) complexes to the blue, when compared to pyrazolate or triazolate analogues. More generally, among the cationic Ir(III) complexes without fluorine substituents on the cyclometalated ligands, 1-3 exhibit the highest-energy MLCT/LLCT emission bands ever reported.
- Monti, Filippo,Baschieri, Andrea,Gualandi, Isacco,Serrano-Perez, Juan J.,Junquera-Hernandez, Jose M.,Tonelli, Domenica,Mazzanti, Andrea,Muzzioli, Sara,Stagni, Stefano,Roldan-Carmona, Cristina,Pertegas, Antonio,Bolink, Henk J.,Orti, Enrique,Sambri, Letizia,Armaroli, Nicola
-
p. 7709 - 7721
(2014/08/05)
-
- Continuous flow generation and reactions of anhydrous diazomethane using a teflon AF-2400 tube-in-tube reactor
-
A continuous process for generation, separation, and reactions of anhydrous diazomethane in a tube-in-tube reactor was developed. The inner tube of the reactor is made of hydrophobic, gas-permeable Teflon AF-2400. The diazomethane is formed in the inner tube and then diffuses through the permeable membrane into the outer chamber and subsequently reacts in the solution carried within. This technique allows safe and scalable reactions with dry diazomethane to be performed on a laboratory scale.
- Mastronardi, Federica,Gutmann, Bernhard,Oliver Kappe
-
supporting information
p. 5590 - 5593
(2013/11/19)
-
- Tetrazoles: LIV. Alkylation of 5-aryltetrazoles under microwave activation
-
The application of microwave activation (MWA) to alkylation of 5-aryltetrazoles with dimethyl sulfate in organic solvents did not considerably affect the selectivity of the process compared to nonactivated procedure. A significant enhancement of the selec
- Efimova,Artamonova,Koldobskii
-
experimental part
p. 725 - 727
(2009/10/11)
-
- Preparation of 1,5-disubstituted tetrazoles under phase-transfer conditions
-
Imidoyl chlorides, obtained by common methods from a wide range of aromatic mono- and diamides, are smoothly converted to the corresponding tetrazoles in high yields by treatment with NaN3 under phase-transfer conditions.
- Artamonova,Zhivich,Dubinskii,Koldobskii
-
p. 1428 - 1430
(2007/10/03)
-
- A Practical Synthesis of 5-Substituted Tetrazoles.
-
Nitrosation of N-formyl amidrazones 8a-g with sodium nitrite - aqueous hydrochloric acid gives tetrazoles 10a-g in good yields.
- Boivin, Jean,Husinec, Suren,Zard, Samir Z.
-
p. 11737 - 11742
(2007/10/02)
-
- A facile and convenient synthesis of substituted tetrazole derivatives from ketones or α,β-unsaturated ketones.
-
Triazidochlorosilane (SiCl4-NaN3 in situ) is a new and efficient reagent for the direct conversion of ketones or α,β-unsaturated ketones to the corresponding tetrazole derivatives in nearly quantitative yield.
- El-Ahl, Abdel-Aziz S.,Elmorsy, Saad S.,Soliman, Hanan,Amer, Fathy A.
-
p. 7337 - 7340
(2007/10/02)
-
- Controlled Synthesis of 5-Substituted 1-Methyl-1H-Tetrazoles and 3,5-Disubstituted 1,4-dimethyltriazolium Salts from N-Methylnitrilium Trifluoromethanesulfonate Salts.
-
C-Alkyl and -benzyl N-methylnitrilium trifluoromethanesulfonate salts, 1C=NMe>+ OTf- (R1=Me, Prn, Pri, But, PhCH2; OTf=O3SCF3), react rapidly under mild conditions with either sodium azide or tetramethylguanidinium azide in nitromethane to give the corresponding 5-substituted 1-methyl-1H-tetrazoles as the sole product in high yields.These reactions are independent of the mode of addition.C-aryl-N-methylnitrilium trifluoromethanesulfonate salts (R1=C6H6, 2-MeC6H4, 4-MeC6H4, 2,4-Me2C6H3) give mixtures of the corresponding tetrazoles and the triazolium salts with sodium azide.With tetramethylguanidinium azide the products depend upon the mode of addition.Addition of the nitrilium salt to the azide gives only the tetrazole, while inverse addition gives the triazolium salt in high yield.
- Amer, Muhanned I. K.,Booth, Brian L.
-
p. 113 - 124
(2007/10/02)
-
- Improved Schmidt synthesis of 1,5-disubstituted 1H-tetrazoles from ketones
-
On treatment with an excess of sodium azide in the presence of titanium(IV) chloride in boiling acetonitrile, both aliphatic and aromatic ketones are smoothly converted to 1,5-disubstituted 1H-tetrazoles in high yields.
- Suzuki,Hwang,Nakaya,Matano
-
p. 1218 - 1220
(2007/10/02)
-
- The conversion of secondary amides to tetrazoles with trifluoromethanesulfonic anhydride and sodium azide
-
Due to the interest in tetrazoles as medicinal agents, a new, mild one-step method for the conversion of amides to tetrazoles employing triphenylphosphine, diethyl azodicarboxylate, and trimethylsilyl azide was recently introduced. An alternate and equally simple method employing trifluoromethanesulfonic anhydride and sodium azide was devised. This method was used to synthesize a series of 1,5-substituted tetrazoles from readily available secondary amides. A 1H-substituted tetrazole was also synthesized by this method from an amide substituted with a cyanoethyl protecting group.
- Thomas
-
p. 767 - 768
(2007/10/02)
-
- Synthesis and Properties of 4H-Imidazoles. Part 2.
-
The 1-(2,2-disubstituted alk-1-enyl)-5-phenyltetrazoles 2 and 4 are prepared from 1-methyl-5-phenyltetrazole and 5-phenyl-1-trimethylsilylmethyltetrazole by formation and appropriate interception of the α-lithioalkyl derivatives.Photolysis of the tetrazoles 2a and 4 gives the stable 4H-imidazoles 9 and 5, respectively.Similar photolysis of the tetrazole 2b gives the tetrazolophenanthrene 12 by an oxidative photocyclisation which is faster than nitrogen extrusion from the tetrazole ring.However, on further irradiation the tetrazolophenanthrene 12 can be transformed into the polycyclic 4H-imidazole 13.The 4H-imidazoles all undergo alkyl or aryl shifts to carbon when heated, 5,7,9 and 13 giving 6,8,10 and 14 respectively.
- Moody, Christopher J.,Rees, Charles W.,Young, Richard G.
-
p. 335 - 339
(2007/10/02)
-
- Reaction of Trimethylsilyl Azide with C=N-O Bond
-
Trimethylsilyl azide (TMSA) was reacted with an oxime ester or a Reissert salt in the presence of trimethylsilyl trifluoromethanesulfonate to give tetrazole derivative.The details of these reactions are examined.
- Nishiyama, Kozaburo,Miyata, Izumi
-
p. 2419 - 2420
(2007/10/02)
-
- ADDITION REACTION OF TRIMETHYLSILYL AZIDE TOWARDS KETONES AND FACILE FORMATION OF TETRAZOLE DERIVATIVES
-
In the presence of Lewis acid such as SnCl2, the reactions of trimethylsilyl azide with ketones readily gave 1:1- or 1:2-adduct, which reacted with Lewis acid to afford tetrazole.
- Nishiyama, Kozaburo,Watanabe, Akio
-
p. 455 - 458
(2007/10/02)
-
- TETRAZOLES. XVI. ALKYLATION OF TETRAZOLES UNDER THE CONDITIONS OF PHASE-TRANSFER CATALYSIS
-
The alkylation of tetrazole and 5-substituted tetrazoles with dimethyl sulfate and methyl iodide in the two-phase methylene chloride-water system in the presence of tetrabutylammonium bromide was investigated.The alkylation of tetrazoles with methyl iodide takes place in the organic phase, while that with dimethyl sulfate takes place both in the organic and in the aqueous phases.The ratio of the isomeric tetrazoles formed during the alkylation of 5-aryltetrazoles by methyl iodide correlate with the substituent constants ?.The use of phase-transfer catalysis during the alkylation of tetrazoles does not lead to a change in the selectivity of the reaction.
- Osipova, T. F.,Ostrovskii, V. A.,Koldobskii, G. I.,Erusalimskii, G. B.
-
p. 357 - 362
(2007/10/02)
-
- TETRAZOLES. XII. EFFECT OF SPECIFIC SOLVATION ON THE RATE AND SELECTIVITY OF ALKYLATION OF 5-PHENYLTETRAZOLE SALTS BY DIMETHYLSULFATE
-
The kinetics of the alkylation of 5-phenyltetrazole potassium salt by dimethysulfate in a mixed acetonitrile-water solvent containing up to 7.6 wt.percent of water were investigated.As the water content of the solvent increases, the alkylation rate decreases and the proportion of 2-methyl-5-phenyl tetrazole in the reaction products increases.During the alkylation of 5-phenyltetrazole lithium, potassium, and cesium salts in aqueous acetonitrile the ratio of the isomeric reaction products does not depend on the nature of the cation which forms the salt.
- Agarkova, L.N.,Ostrovskii, V.A.,Koldobskii, G.I.,Erusalimskii, G.B.
-
p. 903 - 906
(2007/10/02)
-
- TETRAZOLES. VIII. KINETICS AND RATIO OF THE REACTION PRODUCTS IN THE ALKYLATION OF THE SALTS OF SUBSTITUTED 5-PHENYLTETRAZOLES BY DIMETHYL SULFATE IN ACETONITRILE
-
The kinetics and the ratio of the reaction products were investigated for the alkylation of potassium salts of a series of substituted 5-phenyltetrazoles by dimethyl sulfate in acetonitrile.It was shown that with the salt at a concentration of less than 10-3M the corresponding tetrazolate ion enters into reaction with dimethyl sulfate.Electron-withdrawing substituents in the benzene ring reduce the rate of the alkylation reaction and help to increase the proportion of the N2 isomer in the reaction products.The rate constants for the reaction of substituted 5-phenyltetrazoles with dimethyl sulfate and the ratios of the isomeric tetrazoles formed during alkylation correlate with the ? constants of the substituents.
- Ostrovskii, V. A.,Shirobokov, I. Yu.,Koldobskii, G. I.
-
p. 131 - 135
(2007/10/02)
-
- Regiospecific Coordination of Ambidentate Tetrazoles to Cobalt Oximes
-
A series of complexes of the type (n-Bu3P)Co(DH)2(5R-tetrazolate) (DH is the monoanion of dimethylglyoxime; R = CF3, CH3, C6H5, C6H5CH2, (CH3)2N, 4-FC6H4, and 3-FC6H4) have been prepared and characterized by conductance studies, elemental analyses, and 1H, 13C, 31P, and 19F NMR spectroscopy.Quantum-mechanical calculations (MINDO/3) indicate that the N1 nitrogens of the aromatic tetrazolate anion are slightly more nucleophilic than the N2, yet in each complex the ambidentate tetrazolate anion is coordinated to cobalt via the N2 nitrogen, showing that regiospecific coordination is sterically induced.This is in marked contrast to tetrazole complexes of platinum and palladium wherein both N1 and N2 bound tetrazoles are found in approximately equal abundances.These cobalt complexes react with alkyl halides such as CH3I and C6H5CH2Br to produce exclusively 1,5-disubstituted tetrazoles.None of the isomeric 2,5-disubstituted tetrazole is detected in these reactions in marked contrast to the reactions of sodium tetrazolates or gold, palladium, or platinum tetrazolate complexes with alkyl halides which produce mixtures of the 1,5- and 2,5-disubstituted tetrazoles.The crystal structure of n-Bu3PCo(DH)2(5-CF3-tetrazolate) was determined using three-dimensional X-ray diffraction techniques.The molecule crystallizes in the orthorhombic space group Pbca in a unit cell of dimensions a = 12.040(2) Angstroem, b = 21.531(3) Angstroem, c = 23.536(4) Angstroem, ρcalcd = 1.368 g/cm3, ρobsd = 1.374 g/cm3.Refinement converged to 5.4percent with 2525 independent reflections.The tetrazolato ring is coordinated to cobalt via N2 and is planar.The Co-P bond (2.263 Angstroem) is one of the shortest observed in LCo(DH)2X structures.The acute dihedral angle between the planes of the two glyoximato groups (10.4 deg) is among the largest dihedral angles observed in structures of this type.Surprisingly, the tetrazolato ring does not lie in the fold of the two glyoximato rings but is nearly normal to it.Thus, the regiospecificity of the alkylations of the coordinated tetrazolate with alkyl halides is sterically promoted.
- Takach, Nicolas E.,Holt, Elizabeth M.,Alcock, Nathaniel W.,Henry, Ronald A.,Nelson, John H.
-
p. 2968 - 2979
(2007/10/02)
-
- TETRAZOLES. VI. EFFECT OF THE NATURE OF THE CATION ON THE KINETICS AND RATIO OF THE REACTION PRODUCTS IN THE ALKYLATION OF 9-PHENYLTETRAZOLE SALTS BY DIMETHYL SULFATE IN ACETONITRILE
-
It was shown that the sodium, potassium, cesium, and tetrametylammonium salts of 5-phenyltetrazole in acetonitrile are fully dissociated at concentrations of less than 1E-3.During alkylation of the above-mentioned salts with dimethyl sulfate in acetonitrile the reactive particle is 5-phenyltetrazole anion.It was found that ratio of the alkylation products depends on the nature of the cation.The obtained data agree well with a two-stage mechanism for the alkylation of 5-substituted tetrazoles.
- Shirobokov, I. Yu.,Ostrovskii, V. A.,Koldobskii, G. I.
-
p. 691 - 695
(2007/10/02)
-